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81.
Valerie N. Babinsky Fadil M. Hannan Sonia C. Youhanna Céline Maréchal Michel Jadoul Olivier Devuyst Rajesh V. Thakker 《PloS one》2015,10(3)
Background
Cardiovascular disease is the major cause of death in renal transplant recipients (RTRs) and linked to arterial calcification. The calcium-sensing receptor (CaSR), a G-protein coupled receptor, plays a pivotal role in extracellular calcium homeostasis and is expressed in the intimal and medial layers of the arterial wall. We investigated whether common CASR gene variants are predictors for aortic and coronary artery calcification or influence risk factors such as serum calcium, phosphate and glucose concentrations in RTRs.Methods
Two hundred and eighty four RTRs were investigated for associations between three CASR promoter region single nucleotide polymorphisms (SNPs) (rs115759455, rs7652589, rs1501899), three non-synonymous CASR coding region SNPs (A986S, R990G, Q1011E), and aortic and coronary artery calcium mass scores, cardiovascular outcomes and calcification risk factors that included serum phosphate, calcium, total cholesterol and glucose concentrations.Results
Multivariate analysis revealed that RTRs homozygous for the minor allele (SS) of the A986S SNP, when compared to those homozygous for the major allele (AA), had raised serum glucose concentrations (8.7±5.4 vs. 5.7±2.1 mmol/L, P<0.05). In addition, RTRs who were heterozygous (CT) at the rs115759455 SNP, when compared to those homozygous for the major allele (CC), had higher serum phosphate concentrations (1.1±0.3 vs. 1.0±0.2 mmol/L, P<0.05). CASR SNPs were not significant determinants for aortic or coronary artery calcification, and were not associated with cardiovascular outcomes or mortality in this RTR cohort.Conclusions
Common CASR SNPs may be independent predictors of serum glucose and phosphate concentrations, but are not determinants of vascular calcification or cardiovascular outcomes. 相似文献82.
83.
Sigamani Ashokkumar Arunai Nambiraj Sujit Nath Sinha Girigesh Yadav Kothanda Raman Manindra Bhushan Rajesh Thiyagarajan 《Reports of Practical Oncology and Radiotherapy》2015,20(3):170-180
Aim
To measure and compare the head scatter factor for 7 MV unflattened and 6 MV flattened photon beam using a home-made designed mini phantom.Background
The head scatter factor (Sc) is one of the important parameters for MU calculation. There are multiple factors that influence the Sc values, like accelerator head, flattening filter, primary and secondary collimators.Materials and methods
A columnar mini phantom was designed as recommended by AAPM Task Group 74 with high and low atomic number material for measurement of head scatter factors at 10 cm and dmax dose water equivalent thickness.Results
The Sc values measured with high-Z are higher than the low-Z mini phantoms observed for both 6MV-FB and 7MV-UFB photon energies. Sc values of 7MV-UFB photon beams were smaller than those of the 6MV-FB photon beams (0.6–2.2% (Primus), 0.2–1.4% (Artiste) and 0.6–3.7% (Clinac iX (2300CD))) for field sizes ranging from 10 cm × 10 cm to 40 cm × 40 cm. The SSD had no influence on head scatter for both flattened and unflattened beams. The presence of wedge filters influences the Sc values. The collimator exchange effects showed that the opening of the upper jaw increases Sc irrespective of FF and FFF.Conclusions
There were significant differences in Sc values measured for 6MV-FB and unflattened 7MV-UFB photon beams over the range of field sizes from 10 cm × 10 cm to 40 cm × 04 cm. Different results were obtained for measurements performed with low-Z and high-Z mini phantoms. 相似文献84.
85.
Ashwin Mohan Supriya Dabir Naresh Kumar Yadav Matthew Kummelil Rajesh S. Kumar Rohit Shetty 《PloS one》2015,10(4)
Objective
To study the oxygen saturation profile in normal Asian Indian eyes.Design
A cross sectional prospective study.Subjects
Ninety eight consecutive patients presenting to our hospital with best corrected distance visual acuity (BCVA) of 20/20 and a normal ophthalmic examination were included in the study. Patients having any ocular or systemic disease were excluded from the study.Materials and Methods
Oximetry was performed on all subjects with the Oxymap T1 retinal oximeter (Oxymap hf, Reykjavik, Iceland).Main Outcome Measures
The images were analysed for oxygen saturation and diameter.Results
The mean age was 33 years (Range: 18-63; SD: 12.4). The average arteriolar saturation was 90.3 ± 6.6% and the venous saturation was 56.9% ± 6.3. The average A-V (arterio-venous) difference was 33.2% ± 5.2. There was an increase in arteriolar (R2 = 0.264; p=0.001) and venous saturation (R2 = 0.151; p=0.001) with age. There was no significant change in the arterio-venous saturation difference (AVSD). The inferotemporal quadrant had the lowest saturations. Age correlated positively with ocular perfusion pressure (OPP)(R2 = 0.07; p=0.007). OPP correlated positively with global arteriolar saturation (R2=0.057, p=0.018).Conclusion
This study provides the normative database for an Indian population and is comparable to previous studies. Age, vessel diameter and OPP were the significant factors that influenced the saturation. Arteriolar and venous saturations increased with age while the AVSD did not change significantly. 相似文献86.
87.
Rajesh Kumar G Mrudula Spurthi K Kishore Kumar G Mohanalatha Kurapati Saraswati M Mohini Aiyengar T Chiranjeevi P Srilatha Reddy G Nivas S Kaushik P Sanjib Sahu K Surekha Rani H 《PloS one》2015,10(3)
Background
Coronary Artery Disease (CAD) is clearly a multifactorial disease that develops from childhood and ultimately leads to death. Several reports revealed having a First Degree Relatives (FDRS) with premature CAD is a significant autonomous risk factor for CAD development. C - reactive protein (CRP) is a member of the pentraxin family and is the most widely studied proinflammatory biomarker. IL-18 is a pleiotrophic and proinflammatory cytokine which is produced mainly by macrophages and plays an important role in the inflammatory cascade.Methods and Results
Hs-CRP levels were estimated by ELISA and Genotyping of IL-18 gene variant located on promoter -137 (G/C) by Allele specific PCR in blood samples of 300 CAD patients and 300 controls and 100 FDRS. Promoter Binding sites and Protein interacting partners were identified by Alibaba 2.1 and Genemania online tools respectively. Hs-CRP levels were significantly high in CAD patients followed by FDRS when compared to controls. In IL-18 -137 (G/C) polymorphism homozygous GG is significantly associated with occurrence of CAD and Hs-CRP levels were significantly higher in GG genotype subjects when compared to GC and CC. IL-18 was found to be interacting with 100 protein interactants.Conclusion
Our results indicate that Hs-CRP levels and IL-18-137(G/C) polymorphism may help to identify risk of future events of CAD in asymptomatic healthy FDRS. 相似文献88.
89.
90.
Preeti Rajesh Changanamkandath Rajesh Michael D. Wyatt Douglas L. Pittman 《DNA Repair》2010,9(4):458-467
SN1-type methylating agents generate O6-methyl guanine (O6-meG), which is a potently mutagenic, toxic, and recombinogenic DNA adduct. Recognition of O6-meG:T mismatches by mismatch repair (MMR) causes sister chromatid exchanges, which are representative of homologous recombination (HR) events. Although the MMR-dependent mutagenicity and toxicity caused by O6-meG has been studied, the mechanisms of recombination induced by O6-meG are poorly understood. To explore the HR and MMR genetic interactions in mammals, we used the Rad51d and Mlh1 mouse models. Ablation of Mlh1 did not appreciably influence the developmental phenotypes conferred by the absence of Rad51d. Mouse embryonic fibroblasts (MEFs) deficient in Rad51d can only proliferate in p53-deficient background. Therefore, Rad51d?/?Mlh1?/? Trp53?/? MEFs with a combined deficiency of HR and MMR were generated and comparisons between MLH1 and RAD51D status were made. To our knowledge, these MEFs are the first mammalian model system for combined HR and MMR defects. Rad51d-deficient MEFs were 5.3-fold sensitive to N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) compared to the Rad51d-proficient MEFs. A pronounced G2/M arrest in Rad51d-deficient cells was accompanied by an accumulation of γ-H2AX and apoptosis. Mlh1-deficient MEFs were resistant to MNNG and showed no G2/M arrest or apoptosis at the doses used. Importantly, loss of Mlh1 alleviated sensitivity of Rad51d-deficient cells to MNNG, in addition to reducing γ-H2AX, G2/M arrest and apoptosis. Collectively, the data support the hypothesis that MMR-dependent sensitization of HR-deficient cells is specific for O6-meG and suggest that HR resolves DNA intermediates created by MMR recognition of O6-meG:T. This study provides insight into recombinogenic mechanisms of carcinogenesis and chemotherapy resulting from O6-meG adducts. 相似文献